Furniture of the class including childrens' cribs, play yards, etc , are normally sold by having a display in the store, and presenting the purchaser with a generally flat cardboard box of a dimension to accommodate the largest pieces in flat-wise relation stacked on or beneath the other parts. In the case of a crib, the largest parts are the front and rear sides and the mattress support; the two end pieces bearing the corner posts are smaller, and in this case there are two angle irons that help to rigidify the crib. Through a novel interengagement of parts on the corner posts and on the ends of the top and bottom rails of the crib sides, a sturdy crib is provided to be set up by the buyer without the use of extraneous fasteners, often lost, or any tools. The construction is especially attractive because the user can buy a knock-down construction having both front and rear drop sides all self contained with nothing to be done to them except to connect them to the corner posts by means factory installed devices on the corner posts and the top and bottom rails the dropsides.